23 August 2006

6:00 PM

Eight volcanic earthquakes are 212 tremor episodes were detected at Mayon Volcano (13.2576^oN, 123.6856^oE) since 6:00 AM today. The seismic network did not detect any explosion during that observation period. The high tremor count was associated with the activity of extruded lavas, particularly rockfalls and tumbling of lava fragments towards the southeast sector of the volcano, whereas the volcanic earthquakes represented magma ascent and its degassing activity.

Sulfur Dioxide (SO₂) flux of the volcanic plume remained high today, measured at 6,238 tonnes per day (t/d). Moderate volume of white-dirty white steam drifting towards east-northeast was also observed this morning.

Although this eruption episode that began last month has been predominated by lava extrusion and little explosive activity, it is still too early to discount the possibility of hazardous eruption. Even a small but concentrated eruption of pyroclastics and gases when driven by a blast, could easily destroy areas within the eight (8) kilometer radius Extended Danger Zone (EDZ). In this regard, PHIVOLCS maintains Alert Level 4 and that for public safety, all precautions should be maintained. As before, the off-limits area around Mayon includes the 7-kilometer radius EDZ at areas other than the southeast.